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Whoops, I submitted that before I was done. Here is the bracing too. It is definitely different from the Larivee style symmetrical bracing, I am not surprised the modes are different. I have built 3 guitar like this and have been very happy with them. This one is a little different, but mostly just beefing up the transverse brace below the soundhole. I am not worried about what it will sound like but I would be interested if there is anything glaring to you, or anyone else, about the modes. I will be interested to see too what adding the lower bout braces will do to the frequencies. Thanks!

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Burton
http://www.legeytinstruments.com
Brookline, MA.

I think the cross dipole is actually the one at 466. That mode at 336 is another cross grain mode. It never closes up like the dipole does, it is always just three lines running more or less lengthwise with a little "chicken foot" shape right at the tail block.

What is interesting to me is that all of your modes below the ring+ are significantly lower in frequency than mine usually are. And all of the modes above the ring+ are higher. It is also quite interesting that, despite the very unusual bracing pattern, your mode shapes are very similar to mine. I'm sure what that means, perhaps that the plate itself and its shape has a bigger influence on mode shapes than the bracing does?? At least once the bracing is somewhat "in balance" with the plate.

As far as adding braces goes, you don't even have to glue them on to see what effect they will have. You can attach them with double sided tape. The effect on the mode shapes will be nearly the same as gluing. If you like the result you can take it off and glue it on properly.

Overall, I think your modes look good. The plate and the bracing don't seem to be fighting each other and the frequencies are well within acceptable ranges. I would take a bunch of notes on brace positions and heights, finish up the guitar and see how it sounds.

Mark